1. Field of the Invention
The present invention relates generally to a balance valve assembly used in a water control valve, and more particularly to an innovative one which is designed with burn-proof functions.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98.
Given the fact that conventional dual-temperature ceramic valves may lead to transient burning and scalding due to manual error in turning the faucet, and the difficulty in regulating water temperature due to unstable water pressure, an improved structure of a dual-temperature ceramic valve combined with a cold-hot water balance valve has thus been developed in this industry.
In spite of currently available ceramic products and relevant patents based on balance valves, some shortcomings and disadvantages still exist.
A conventional balance valve generally comprises a fixed valve pipe and a moveable spool. Of which, a through-hole is set separately at both ends of the fixed valve pipe, and an opening arranged separately at its both sides so as to guide cold and hot water. An inner groove is formed separately at both ends of the moveable spool, and separated by a partition. Moreover, these two inner grooves are provided with an opening connected with that of the fixed valve pipe. With this structure, when cold and hot water separately pass through two inner grooves of the moveable spool via the openings at both sides of the fixed valve pipe, the moveable spool will yield reciprocating transverse movement with the variation of cold/hot water streams' flow velocity, based on the principle of higher velocity versus smaller pressure and smaller velocity versus bigger pressure as well as the property of water flow. This will change the sectional connection area between the moveable spool and the openings at both sides of the fixed valve pipe, serving the purpose of auto balancing of cold/hot water temperature.
However, the following shortcomings of typical balance valves are found during actual applications:
First, when a faucet is turned manually to full hot water mode, cold water passing the balance valve will be fully blocked, and the water flow is under a stagnant state. In such a case, the moveable spool in the balance valve will be shifted towards the hot water side until the preset end due to bigger pressure at cold water side, so the sectional area of hot water flow channel will be minimized. However, hot water stream cannot be fully blocked off, namely, hot water stream will continuously flow out of the faucet along the hot water flow channel of the ceramic valve, leading to scalding of the users. As most of users believe that the so-called faucet of balance structure could avoid scalding, accurate temperature control is often neglected, giving prominence to the structural design of such balance valve for safety guarantee.
Second, and on the other hand, if a conventional dual-temperature ceramic valve is combined with the cold-hot water balance valve, and the faucet is fully turned to full cold water mode, the shift direction of the moveable spool in the balance valve will almost block off the cold water flow channel, affecting heavily or even leading to loss of cold water supply function of the faucet.
Thus, to overcome the aforementioned problems of the prior art, it would be an advancement if the art to provide an improved structure that can significantly improve the efficacy.
Therefore, the inventor has provided the present invention of practicability after deliberate design and evaluation based on years of experience in the production, development and design of related products.